Cumulative Risk Impact of RET, SEMA3, and NRG1 Polymorphisms Associated With Hirschsprung Disease in Han Chinese

Transcriptome profiling of intact bowel wall reveals that PDE1A and SEMA3D are possible markers with roles in enteric smooth muscle apoptosis, proliferative disorders, and dysautonomia in Crohn's disease

Background: Inflammatory bowel disease (IBD) is a complex and multifactorial inflammatory condition, comprising Crohn's disease (CD) and ulcerative colitis (UC). While numerous studies have explored the immune response in IBD through transcriptional profiling of the enteric mucosa, the subtle distinctions in the pathogenesis of Crohn's disease and ulcerative colitis remain insufficiently understood. Methods: The intact bowel wall specimens from IBD surgical patients were divided based on their inflammatory status into inflamed Crohn's disease (iCD), inflamed ulcerative colitis (iUC) and non-inflamed (niBD) groups for RNA sequencing. Differential mRNA GO (Gene Ontology), and KEGG (Kyoto Encyclopedia of Genes and Genomes), and GSEA (Gene Set Enrichment Analysis) bioinformatic analyses were performed with a focus on the enteric autonomic nervous system (ANS) and smooth muscle cell (SMC). The transcriptome results were validated by quantitative polymerase chain reaction (qPCR) and immunohistochemistry (IHC). Results: A total of 2099 differentially expressed genes were identified from the comparison between iCD and iUC. Regulation of SMC apoptosis and proliferation were significantly enriched in iCD, but not in iUC. The involved gene PDE1A in iCD was 4-fold and 1.5-fold upregulated at qPCR and IHC compared to that in iUC. Moreover, only iCD was significantly associated with the gene sets of ANS abnormality. The involved gene SEMA3D in iCD was upregulated 8- and 5-fold at qPCR and IHC levels compared to iUC. Conclusion: These findings suggest that PDE1A and SEMA3D may serve as potential markers implicated in enteric smooth muscle apoptosis, proliferative disorders, and dysautonomia specifically in Crohn's disease.

Association of rs2435357 and rs2506030 polymorphisms in RET with susceptibility to hirschsprung disease: A systematic review and meta-analysis

BACKGROUND

There are numerous published studies on the association between RET polymorphisms and susceptibility to Hirschsprung disease (HSCR). However, some of the results are inconsistent and the studies were conducted with small sample sizes. Therefore, we performed a meta-analysis to clarify the relationship.

METHODS

Relevant data were retrieved from PubMed, Web of Science, Cochrane Library, EMBASE, CNKI, and Google Scholar according to PRISMA guidelines. Odds ratios (OR) were calculated to assess susceptibility to HSCR. Meanwhile, heterogeneity and publication bias were also calculated by R software package (version 4.2.1). The protocol was published in PROSPERO (CRD42022348940).

RESULTS

A total of 12 studies were included in the meta-analysis and comprised 12 studies on the RET polymorphism rs2435357 (1,939 subjects and 3,613 controls) and 7 studies on the RET polymorphism rs2506030 (1,849 patients with HSCR and 3,054 controls). The analysis revealed that rs2435357 [A vs. G: odds ratio (OR) = 3.842, 95% confidence interval (CI) 2.829-5.220; AA vs. GG: OR = 2.597, 95% CI 1.499-4.501; AA + AG vs. GG: OR = 6.789, 95% CI 3.0711-14.9973; AA vs. AG + GG: OR = 8.156, 95%CI 5.429-12.253] and rs2506030 (A vs. G: OR = 0.519, 95% CI 0.469-0.573; AA vs. GG: OR = 0.543, 95% CI 0.474-0.623; AA + AG vs. GG: OR = 0.410, 95% CI 0.360-0.468; AA vs. AG + GG: OR = 0.361, 95%CI 0.292-0.447) were significantly associated with susceptibility to HSCR.

CONCLUSIONS

The polymorphisms rs2435357 and rs2506030 in the RET may be related to susceptibility to HSCR, of which rs2435357 (T > C) is the causal locus and rs2506030 (A > G) is the protective locus.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/prospero/, identifier:CRD42022348940.

Multiple, independent, common variants at RET, SEMA3 and NRG1 gut enhancers specify Hirschsprung disease risk in European ancestry subjects

PURPOSE

Hirschsprung disease (HSCR) is a developmental disorder of the enteric nervous system (ENS) characterized by congenital aganglionosis arising from coding variants in ENS genes causing partial or total loss-of-function. Low-penetrance, common, noncoding variants at RET, SEMA3 and NRG1 loci are also associated with HSCR, with small-to-moderate loss of gene expression mediated through sequence variants in cis-regulatory elements (CRE) as another causal mechanism. Since these latter variants are common, many individuals carry multiple risk variants. However, the extent and combinatorial effects of all putative CRE variants within and across these loci on HSCR is unknown.

METHODS

Using 583 HSCR subjects, one of the largest samples of European ancestry studied, and genotyping 56 tag variants, we evaluated association of all common variants overlapping putative gut CREs and fine-mapped causal variants at RET, SEMA3 and NRG1.

RESULTS

We demonstrate that 28 and 8 tag variants, several of which are genetically independent, overlap putative-enhancers at the RET and SEMA3 loci, respectively, as well as two fine-mapped tag variants at the NRG1 locus, are significantly associated with HSCR. Importantly, disease risk increases with increasing numbers of risk alleles from multiple variants within and across these loci, varying >25-fold across individuals.

CONCLUSION

This increasing allele number-dependent risk, we hypothesize, arises from HSCR-relevant ENS cells sensing the reduced gene expression at multiple ENS genes since their developmental effects are integrated through gene regulatory networks.

Association of Neuregulin 1 rs7835688 G > C, rs16879552 T > C and rs2439302 G > C Polymorphisms with Susceptibility to Non-Syndromic Hirschsprung's Disease

Hirschsprung's disease (HSCR) is a heterogeneous congenital malformation of the enteric nervous system with a complex genetic etiology. We investigated if there was an association between Neuregulin-1 (NRG1) rs7835688 G > C, rs16879552 T > C and rs2439302 G > C polymorphisms and the risk of HSCR. Methods: We determined and compared the frequency of NRG1 polymorphisms rs7835688 G > C, rs16879552 T > C and rs2439302 G > C in 70 children with HSCR and 90 controls by TaqMan SNPs genotyping assays. Results: No significant differences in allele or genotype frequencies of NRG1 rs7835688 G > C, rs16879552 T > C and rs2439302 G > C polymorphisms were observed between HSCR cases and controls. Analyses showed that the NRG1 rs7835688 G > C, rs16879552 T > C and rs2439302 G > C polymorphisms were not significantly associated with an increased risk of non-syndromic HSCR. Conclusions: Our findings suggested that NRG1 rs7835688 G > C, rs16879552 T > C and rs2439302 G > C polymorphisms are not a risk factor in development of HSCR.

Effect of semaphorin 3C gene variants in multifactorial Hirschsprung disease

OBJECTIVE

Cluster genes, specifically the class 3 semaphorins (SEMA3) including SEMA3C, have been associated with the development of Hirschsprung disease (HSCR) in Caucasian populations. We aimed to screen for rare and common variants in SEMA3C in Indonesian patients with HSCR.

METHODS

In this prospective clinical study, we analyzed SEMA3C gene variants in 55 patients with HSCR through DNA sequencing and bioinformatics analyses.

RESULTS

Two variants in SEMA3C were found: p.Val337Met (rs1527482) and p.Val579 =  (rs2272351). The rare variant rs1527482 (A) was significantly overrepresented in our HSCR patients (9.1%) compared with South Asian controls in the 1000 Genomes (4.7%) and Exome Aggregation Consortium (ExAC; 3.5%) databases. Our analysis using bioinformatics tools predicted this variant to be evolutionarily conserved and damaging to SEMA3C protein function. Although the frequency of the other variant, rs2272351 (G), also differed significantly in Indonesian patients with HSCR (27.3%) from that in South Asian controls in 1000 Genomes (6.2%) and ExAC (4.6%), it is a synonymous variant and not likely to affect protein function.

CONCLUSIONS

This is the first comprehensive report of SEMA3C screening in patients of Asian ancestry with HSCR and identifies rs1527482 as a possible disease risk allele in this population.

Association of REarranged during Transfection (RET) c.73 + 9277T > C and c.135G > a Polymorphisms with Susceptibility to Hirschsprung Disease: A Systematic Review and Meta-Analysis

Background: Previous studies have suggested a close association between REarranged during Transfection (RET) c.73 + 9277T > C and c.135G > A polymorphisms and Hirschsprung disease (HSCR) susceptibility. The results are inconsistent and contradictory. Thus, we performed a meta-analysis to evaluate the association of RET c.73 + 9277T > C and c.135G > A polymorphisms with risk of HSCR.Methods: The eligible literatures were searched by PubMed, Google Scholar, EMBASE, and CNKI up to August 5 2019.Results: A total of 20 studies including 10 studies with 1136 cases and 2420 controls on c.73 + 9277T > C and 10 studies with 917 cases and 1159 controls on c.135G > A were selected. Pooled ORs revealed that c.73 + 9277T > C and c.135G > A polymorphisms were significantly associated with an increased risk of HSCR. Moreover, stratified analysis revealed that c.73 + 9277T > C and c.135G > A polymorphisms were associated with HSCR risk in Asian, Caucasian and Chinese populations.Conclusions: This meta-analysis result indicated that the RET c.73 + 9277T > C and c.135G > A polymorphisms were associated with susceptibility to HSCR.

Distinctive genetic variation of long-segment Hirschsprung's disease in Taiwan

BACKGROUND

Hirschsprung's disease (HSCR) is a congenital disorder with the absence of myenteric and submucosal ganglion cells within distal gut. Due to multigenic inheritance and interactions, we employed next-generation sequencing (NGS) to investigate genetic backgrounds of long-segment HSCR (L-HSCR) in Taiwan.

METHODS

Genomic DNA extracted from peripheral blood of L-HSCR patients was subjected to capture-based NGS, based on a 31-gene panel. The variants with allele frequency <0.05 and predicted by computational methods as deleterious were further validated by Sanger sequencing in patients and their family as well to tell de novo from inherited variants.

RESULTS

Between 2015/04 and 2018/05, this study enrolled 23 L-HSCR patients, including 15 (65.2%) sporadic cases and 8 (34.8%) familial patients in 4 different families. Six sporadic and seven familial cases showed possible harmful variants across eight different genes, accounting for an overall detection rate of 56.5%. These variants mainly resided in SEMA3C, followed by RET, NRG1, and NTRK1. Three sporadic and 2 familial cases exhibited strong pathogenic variants as a deletional frameshift or stop codon in RET, L1CAM or NRG1. In a HSCR family, the father passed on a pathogenic RET frameshift to two daughters; however, only one developed HSCR.

CONCLUSION

Using NGS, we disclosed deleterious mutations such as a frameshift or stop codon in either familial or sporadic patients. Our cases with isolated L-HSCR or even total colonic aganglionosis appeared to exhibit complex patterns of inheritance and incomplete penetrance even in families with the same genetic variants, reflecting the possible effects of environmental factors and genetic modifiers.

ASSOCIATION OF RS2435357 AND RS1800858 POLYMORPHISMS IN RET PROTO-ONCOGENE WITH HIRSCHSPRUNG DISEASE: SYSTEMATIC REVIEW AND META-ANALYSIS

Introduction:

Many published studies have estimated the association of rs2435357 and rs1800858 polymorphisms in the proto-oncogene rearranged during transfection (RET) gene with Hirschsprung disease (HSCR) risk. However, the results remain inconsistent and controversial.

Aim:

To perform a meta-analysis get a more accurate estimation of the association of rs2435357 and rs1800858 polymorphisms in the RET proto-oncogene with HSCR risk.

Methods:

The eligible literatures were searched by PubMed, Google Scholar, EMBASE, and Chinese National Knowledge Infrastructure (CNKI) up to June 30, 2018. Summary odds ratios (ORs) and 95% confidence intervals (CIs) were used to evaluate the susceptibility to HSCR.

Results:

A total of 20 studies, including ten (1,136 cases 2,420 controls) for rs2435357 and ten (917 cases 1,159 controls) for rs1800858 were included. The overall results indicated that the rs2435357 (allele model: OR=0.230, 95% CI 0.178-0.298, p=0.001; homozygote model: OR=0.079, 95% CI 0.048-0.130, p=0.001; heterozygote model: OR=0.149, 95% CI 0.048-0.130, p=0.001; dominant model: OR=0.132, 95% CI 0.098-0.179, p=0.001; and recessive model: OR=0.239, 95% CI 0.161-0.353, p=0.001) and rs1800858 (allele model: OR=5.594, 95% CI 3.653-8.877, p=0.001; homozygote model: OR=8.453, 95% CI 3.783-18.890, p=0.001; dominant model: OR=3.469, 95% CI 1.881-6.396, p=0.001; and recessive model: OR=6.120, 95% CI 3.608-10.381, p=0.001) polymorphisms were associated with the increased risk of HSCR in overall.

Conclusions:

The results suggest that the rs2435357 and rs1800858 polymorphisms in the RET proto-oncogene might be associated with HSCR risk.

Combined Genetic Effects of RET and NRG1 Susceptibility Variants on Multifactorial Hirschsprung Disease in Indonesia

BACKGROUND

Specific genetic variants at RET (rs2435357) and NRG1 (rs7835688, rs16879552) are associated with Hirschsprung disease (HSCR) in Indonesia. This study aimed to investigate the additional effect of RET rs2506030 on these variants to determine its potential interactions in HSCR patients of Indonesian ancestry.

METHODS

Sixty HSCR patients and 122 non-HSCR controls were ascertained for this study and genotyped for RET rs2506030 using the TaqMan assay.

RESULTS

RET rs2506030 was associated with HSCR both by case-control analysis (odds ratio = 1.68; P = 0.043) and the transmission disequilibrium test (P = 0.034). Furthermore, individuals with five or six risk alleles at RET rs2506030, rs2435357 and NRG1 rs7835688 showed ∼45-fold higher HSCR risk than those with 0 or 1 or 2 risk alleles.

CONCLUSIONS

Disease risk of HSCR is increased by the combination of specific RET and NRG1 susceptibility variants.

Significance of neurexin and neuroligin polymorphisms in regulating risk of Hirschsprung's disease

By performing a basic case-control study among a Chinese population, the aims of this study were to explore if single nucleotide polymorphisms (SNPs) within neurexin and neuroligin were associated with susceptibility to Hirschsprung's disease (HD). Eleven SNPs within neurexin and neuroligin were selected in this basic case-control study, and this study recruited 210 children with HD and 187 healthy children. The t-test and Χ² test were used to find the difference between case and control in their clinical variables. OR and 95% CI were used to assess the association between HD susceptibility and neurexin/neuroligin polymorphisms/haplotypes. Several SNPs were significantly associated with altered risk of HD in the Chinese Han population, including rs1421589 within NRXN1, rs11795613 and rs4844285 within NLGN3, as well as rs5961397, rs7157669 and rs724373 within NLGX4X (all P<0.05). Further studies presented that the effects of rs1421589 within NRXN1, rs4844285 and rs11795613 within NLGN3, as well as rs5961397 within NLGX4X on HD phenotypes were also statistically significant (all P<0.05). Conclusively, the polymorphisms and haplotypes situated within neurexin and neuroligin were markedly associated with the onset of HD, implying that mutations of neurexin and neuroligin might serve as the treatment target for HD for the Chinese children.

Association of NRG1 and AUTS2 genetic polymorphisms with Hirschsprung disease in a South Chinese population

Hirschsprung disease (HSCR) is a genetic disorder characterized by the absence of enteric ganglia. There are more than 15 genes identified as contributed to HSCR by family-based or population-based approaches. However, these findings were not fulfilled to explain the heritability of most sporadic cases. In this study, using 1470 HSCR and 1473 control subjects in South Chinese population, we replicated two variants in NRG1 (rs16879552, P = 1.05E-04 and rs7835688, P = 1.19E-07), and further clarified the two replicated SNPs were more essential for patients with short-segment aganglionosis (SHSCR) (P = 2.37E-05). We also tried to replicate the most prominent signal (rs7785360) in AUTS2, which was a potential susceptibility gene with HSCR. In our results, in terms of individual association, marginal effect was observed to affect the HSCR patients following recessive model (P = 0.089). Noteworthy, significant intergenic synergistic effect between rs16879552 (NRG1) and rs7785360 (AUTS2) was identified through cross-validation by logistic regression (P = 2.45E-03, OR = 1.53) and multifactor dimensionality reduction (MDR, P < 0.0001, OR = 1.77). Significant correlation was observed between expression of these two genes in the normal segments of the colons (P = 0.018), together with differential expression of these genes between aganglionic colonic segments and normal colonic segments of the HSCR patients (P value for AUTS2 <0.0001, P value for NRG1 = 0.0243). Although functional evaluation is required, we supply new evidence for the NRG1 to HSCR and raised up a new susceptibility gene AUTS2 to a specific symptom for the disease.

Effects of NRG1 Polymorphisms on Hirschsprung's Disease Susceptibility: A Meta-analysis

Substantial resources have been devoted to evaluate the relationship between NRG1 variants rs7835688 and rs16879552 and Hirschsprung’s Disease (HSCR) but no consistency exists. This meta-analysis aimed to assess the association between the two SNPs and HSCR. PubMed, EMBASE, and Chinese Biological Medicine databases were searched for studies potentially eligible up to March, 2017. The summary odds ratios (ORs) with 95% CIs were calculated from different genetic models. Nine case-control studies (8 for both and 1 for rs16879552 only) involving 1984 HSCR patients and 4220 controls were identified. The combined results showed a significant association between HSCR risk and rs7835688 in all genetic models (per-allele model: OR = 1.66, 95% CI = 1.35–2.05; P = 1.940E-06). Rs16879552 was significantly associated with HSCR in per-allele (OR = 1.50, 95% CI = 1.27–1.76; P = 1.087E-06), additive and recessive model, except for dominant model. Stratified analysis by ethnicity showed that rs7835688 and rs16879552 were only causative for Asians, but not risk locus for Caucasians. Furthermore, pooled data based on segment length indicated that individuals with rs7835688 experienced a significantly higher risk for short-segment HSCR in all genotypes; but rs16879552 was only found to be associated with long-segment HSCR/ total colonic aganglionosis at the allele level.

Effects of RET, NRG1 and NRG3 Polymorphisms in a Chinese Population with Hirschsprung Disease

The RET proto-oncogene was identified as a major locus involved in Hirschsprung disease (HSCR). A genome-wide association study (GWAS) and whole exome sequencing identified NRG1 and NRG3 as additional HSCR susceptibility loci. We investigated the effects of RET (rs2506030 and rs2435357), NRG1 (rs2439302, rs16879552 and rs7835688) and NRG3 (rs10748842, rs10883866 and rs6584400) polymorphisms in a Chinese population with HSCR. We assessed single nucleotide polymorphisms (SNPs) in the RET, NRG1 and NRG3 genes in a cohort of 362 sporadic HSCR patients and 1,448 normal controls using a TaqMan genotyping assay. Significant associations were found between HSCR risk and rs2506030, rs2435357, rs2439302 and rs7835688 (odds ratio [OR] 1.64, P = 1.72E-06; 2.97, P = 5.15E-33; 1.84, P = 9.36E-11; and 1.93, P = 1.88E-12, respectively). Two locus analyses of SNPs indicated increased disease risks of HSCR between NRG1 rs2439302 and RET rs2435357 or rs2506030. RET rs2506030 (GG genotype) and rs2435357 (TT genotype), in combination with NRG1 rs2439302 (GG genotype), were strongly associated with the highest risk of HSCR (OR = 56.53, P = 4.50E-07) compared with the two loci or a single SNP of either RET or NRG1. Our results support the association between genetic variation of RET and NRG1 and susceptibility to HSCR in the Chinese population.